You got a prescription for a retinol — or may you just picked up an over-the-counter version from Sephora. We don't blame you, retinols really can be a miraculous product. But, if you're really into skin-care ingredients or taking care of your skin in general, you probably wonder about which products and ingredients will work best with your new retinol... and which ones won't. The thought has crossed my mind before using my much loved Sunday Riley Luna ($105; sephora.com).

To find out what was what, I reached out to renowned dermatologist Dr. Craig Austin, who also happens to be the founder of one of my favorite skin-care brands, Cane & Austin. The Miracle+ Pads? Actually a miracle.

First and foremost, Dr. Austin reiterated to me one key fact: If you are using a retinol, an SPF is non-negotiable, since vitamin A (aka retinol) makes your skin more sensitive to the sun. Additionally, if you are some who is photosensitive or has eczema, Dr. Austin wouldn't recommend a retinol for you.

Other people who should avoid vitamin A skin-care? Women who are pregnant or breast-feeding.

So what about a product with a BHA, like a salicylic acid? Dr. Austin told me, "Sometimes, but it's sometimes not compatible with your skin."

But a product that is super compatible with your retinol? Glycolic acid. Dr. Austin also advised me that when using a glycolic and a retinol, alternate between them, using one in the morning and one in the evening. But, at the end of the day, they are a nice pairing.

One thing that Dr. Austin stressed was that "a retinol or a retin-a help your other skin-care products penetrate much deeper, and therefore help them to be generally more effective."

So, if you are using a topical antibiotic for acne treatment, using that in tandem with your retinol might yield better results.